If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

How do I bond Rubber to steel?

Anyone have a fool proof method for bonding Hard rubber to steel?
Have some 80 durometer rubber sheets I would like to use for handle scale material.
What would be the best way to bond it, so it will stand up on a heavy use blade?

80 Duro should hold up ok, as there's a lot of neoprene handles out there these days....

You'll need to flatten and rough the side that's touching the steel (I'd recommend bead/sand blasting both the handles (tape off sections you don't want blasted) and the scales...

Then, use an epoxy with a longer cure time (not the 30 minute stuff)..... You should be fine with that. 3m also has some stuff (durabond I think) that will hold anything, just don't get it on yourself......

When I did neoprene to steel, I avoided all epoxies. Most are simply too brittle for a material that will flex like rubber.

I eventually found myself in an autobody store and asked what they use to bond carbody accessories to sheet metal on the exterior of cars. he sold me a tube of black adhesive that dries almost the same flexibility as neoprene.

I think mainly you are just sealing...I know the neoprene handles I did hardly even needed to be glued. Even after drilling, I had to drive the pins into the holes and upon test-fitting, it was a bitch to get the handles back off even without glue since the neoprene held the pins so snugly.

I haven't tried everything, but I had an application where I had to bond to rubber in a production application. It can be tricky because the wax processing aids used in rubber. We had adhesive reps come out and I even talked to engineers at 3M and Loctite. For our application we had the best luck with a super glue. The best was:

3M pronto CA40H. It is about $20 an ounce.

But we ended up using something by 3bond because it worked almost as well an was much less expensive

Thanks for the advice...tried contact cement and it bonded the rubber together very well, still need to try bonding it to steel.
Also tried K&G 24hr epoxy and that worked but did not stand up to the "Whack it against the cement test" very well. held to the steel but there was a clean break at the rubber. No evidence that it had really gripped the rubber well.
Your obsevations are correct a hard/brittle epoxy bond is not compatible with flexable material like rubber.
Will give RTV a try tonight and post the results tomoorrow.
My reservation with Superglue is the whole Moisture/Water and shock issue of it failing as a bonding agent.